Electric lamp socket for elongated tubular lamps



T. WOLD 2,555,524

ELECTRIC LAMP SOCKET FOR ELONGATED TUBULAR LAMPS June 5, 1951 Filed Nov.21, 1949 bmnfnr 7 wave Maw Patented June 5, 1951 UNITED STATES ELECTRICLAMP SOCKET FOR ELONGATED TUBULAR LAlVIPS Trygve Wold, Georgetown,Ontario, Canada, as-

signor to Smith & Stone Limited, Georgetown,

Ontario, Canada PATENT OFFICE 1 Claim.

This invention relates to sockets for tubular electric lamps, such asfluorescent lamps, having a plurality of aligned contact pins at eachend.

Sockets of this type are positioned at each end of a fixture and eachsocket has a foot of a standard shape which fits into the underside ofthe fixture, suspending the sockets lamp opening below the foot andallowing the lamp to be inserted or removed by a person standing beneaththe fixture.

The sockets which have been in common use, for example in tubularfluorescent lamp fixtures, consist of an insulating base having a lampopening in one face and resilient contact members. The lamp opening hasa neck-like portion extending to an edge and adapted to pass contactpins longitudinally to the opening proper which is adapted to permitrotation of the lamp and thus of the contact pins. The resilientcontacts are formed with V sections and spaced one at each side of thelamp opening so that when the lamp is rotated (usually a quarterrevolution) the pins become seated in the bottom of the V sections.

The fluorescent lamps which these sockets are used to support within afixture, are about three feet long and of considerable weight. Since thefixtures are usually supported near the ceiling and are open at thebottom, it is necessary to insert the tube from the bottom edge of thesocket and then to rotate it a quarter revolution within the opening inthe sockets base to bring the pins into the V section of the contacts.When inserting these lamps it has been found to be very difficult toposition them properly in the bottom of the V sections since the weightof the lamp makes it difiicult, if not impossible, to feel the contactpins become seated. Often a lamp is left without all pins seated becausethe lamp has been turned more or less than one quarter revolution, andit subsequently falls from the fixture exposing people in the vicinityto flying particles of glass as the lamp explodes on the floor.

According to the present invention, the disadvantages of the prior arthave been avoided by providing a lamp socket for electric lamps having aplurality of aligned contact pins which comprises an insulating base, anopening in one face of the base having a neck portion extending to anedge of the base and adapted to pass aligned contact pinslongitudinally, and an enlarged portion adapted to permit rotation ofthe lamp base having aligned pins thereon, resilient contact membersspaced within the opening and adapted to engage the contact pins whenthe lamp is rotending to an edge of the base ll.

tated and means adapted positively to stop rotation of the lamp beforethe pins return to alignment with the neck portion of the opening.

When inserting the lamp into a fixture having sockets according to thepresent invention, the lamp is raised up into the fixture until itscontact pins are within the openings in the sockets, and then it isrotated until the pins contact the means adapted positively to stoprotation. These means may consist of a projection on at least one of thecontact members.

The invention will now be described by reference to the accompanyingdrawings which illustrate an embodiment of it and in which:

Figure 1 is a view of a tubular lamp held by two sockets of the typereferred to,

Figure 2 is a front view of a socket according to the invention,

Figure 3 is a rear view,

Figure 4 is an enlarged cross section on the line 4-4 of Figure 2,

Figure 5 is an enlarged view of part of the socket as shown in Figure 2.

A socket I0 according to the invention consists of a conventionalinsulating base ll of plastic material moulded with a circular openingI2 in the front face thereof and a narrow neck H ex- A foot I5 is of thestandard shape for fitting into a light fixture. Resilient contactmembers It are housed in the usual way in a cavity I! at the rear of thebase H, which cavity ll joins with the opening [2 allowing the contactmembers Iii to pass through the opening l2 at either side of a guidepost [8. Each of the contact members It has a broad U-shaped section l9formed in it opposite the guide post 18, and a projection 29 is formedat the centre of each U section [9 and extends into a slot 2| in eitherside of the guide post [8. The guide post 18 has a slot 22 ofapproximately the same width as the neck 14. Screws 23, within the footl5, thread into the contact members 16 for attachment to the wiring ofthe fixture, and a removable insulating strip 21 covers the back of thecavity H.

The sockets II] are held in the position shown in Figure 1 when mountedon a fixture (not shown) and lamp 24 is supported between them. Aplurality of aligned contact pins 25 is provided at each end 26 of thelamp 24 and the lamp is put into the fixture by inserting the alignedpins longitudinally into the neck 14 of each socket and pushing the lamp24 up into the fixture until the first of the contact pins 25 has passedthrough the slot, and the pins 25 straddle the guide post la. The lamp24 is then rotated in either direction causing the contact pins to enterthe U- shaped sections [9 and engage the projections 26 which positivelystop the aligned pins 25 rotatleft in the fixture Without danger of itsubse quently falling therefrom. 7

What I claim as my invention is A socket for electric lamps having aplurality ofaligned contact pins, comprising an insulating base, anopening in one face of the base having a-neck portion extending to anedge ofthe base and adapted to pass a plurality of aligned contact pinslongitudinally, a. guide postjhavingslots therein and an. enlargedportionadapted to per- 4 mit rotation of the lamp, resilient contactmembers spaced within the opening and adapted to engage the contact pinswhen the lamp is rotated, each of saideontact members having a broad,U-shaped section formed in it opposite the said guide post, and meanscentrally disposed on each of said U-shaped sections extending into thesaid slots in the guide post adapted positively to stop rotation of thelamp before the said pins return to alignment with the neck portion ofthe open- Ling.

TRYGVE WOLD.

REFERENCES CITED UNITED STATES PATENTS Number Name Date 20 2,137,174Marshous Nov. 15, 1938 $252,340 Bryant et al. 1 Aug. 12,1941 2,510,628Goebel -June- 6, 19 50

